Inter-vehicle communications systems have been developed and are in use to enable communications between vehicles while traveling on roads. However, conventional inter-vehicle communications systems use the same channel regardless of each vehicle's traveling direction (i.e., regardless of whether the vehicles are on the same side or the opposing side of the road). Therefore, such systems have a drawback in that driving information about vehicles traveling on the opposing side, which is useless for driving, is received as well as driving information about vehicles traveling on the same side, which is useful for driving. Thus, there is a need for a technology that makes it possible for a moving vehicle to receive driving information about vehicles traveling on a road without receiving driving information about vehicles traveling on the opposing side of the road.